By Anne Bartosewicz, Northeast Utilities, and J. Brett Williams and Jim Hogan, Burns & McDonnell

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2 By Anne Bartosewicz, Northeast Utilities, and J. Brett Williams and Jim Hogan, Burns & McDonnell CONNECTICUT LIGHT & POWER SERVES ONE OF THE MOST POWER-CONSTRAINED REGIONS IN THE UNITED STATES. Recognizing the need to meet the area s growing demand for power, CL&P (Berlin, Connecticut, U.S.), a wholly owned subsidiary of Northeast Utilities (NU; Hartford, Connecticut), is strengthening the transmission capacity to the southwest part of the state. The result is the Middletown-Norwalk Project (MNP), which is now one of the largest transmission projects in the history of this industry. MODEL SELECTION At first, CL&P considered the two standard methods used for accomplishing major construction projects: the design-bid-build approach and the design-build approach. In the design-bid-build model, CL&P would act as general contractor, manage the project with internal resources and assume all responsibilities including hiring design engineers, procuring materials and equipment, developing construction work scopes and hiring contractors. Under the design-build approach, also known as engineerprocure-construct (EPC) or turnkey, CL&P would define a construction project and hire a design-build team to assume responsibility for engineering, procurement, construction and coordination of the work. As the owner, CL&P would still manage the project, but leave construction management details to the general contractor. As the scope of the MNP emerged and construction costs and timelines came into sharper focus, the utility realized the project was too critical and complex to manage entirely with existing internal resources. CL&P desired a new approach where it could manage the overall project without adding significant internal resources. CL&P determined that a partnership with a firm that was a recognized expert in the design and construction of transmission facilities was the path to a successful project. Engineering and construction firm Burns & Mc- Donnell (Kansas City, Missouri, U.S.) recognized CL&P s challenge and offered an innovative solution, the concept known as program management: a proven solution in other industries for managing complex, large-scale and capital projects. Under the program management model, the owner hires a firm that serves as the owner s manager, or agent, to oversee the entire process from design through construction. Although the program manager works for the owner, a partnership is developed with a strong focus on flexibility.

3 CL&P implements a new approach for a major system upgrade project. MIDDLETOWN-NORWALK PROJECT SUMMARY 45 miles (72 km) of new overhead 345-kV line 24 miles (38 km) of new underground 345-kV line 56 miles (90 km) of reconstructed overhead 115-kV line 1 mile (2 km) of new underground 115-kV line 2 new substations 1 new switching station 1 upgraded substation 1 upgraded switching station 18 Connecticut municipalities along route: Middletown Cheshire Milford Haddam Hamden Stratford Durham Bethany Bridgeport Middlefield Woodbridge Fairfield Meriden Orange Westport Wallingford West Haven Norwalk Note: United Illuminating Co. (New Haven, Connecticut, U.S.) is a 20% partner with CL&P on this project and will own 6.5 miles (10 km) of the underground 345-kV line and one of the new substations. PROGRAM MANAGEMENT IMPLEMENTATION In this case, the program manager assisted with the initial project design, then formulated an execution plan that identified the scope of construction and the strategy for contracting for the various parts of the project. The result was a master plan for CL&P s US$1.05 billion share of the MNP, which started construction in April 2006 and is scheduled for completion by December Program management is most successful because tasks such as planning, permitting, design and construction are advanced simultaneously whenever possible, rather than in a linear fashion. A program manager has intimate knowledge of every activity, enabling the direction and allocation of resources to support the master plan. In this case, the program manager has specific contractual functions: Real estate acquisition. Most of the MNP will be constructed on public streets and other existing rights-of-way (ROW). However, the project will require purchasing some privately owned land and easements to accommodate portions of the project and to provide construction access. The program management team works with CL&P s land acquisition team to manage the timing of land and easement purchases to support construction sequencing. Permitting and environmental planning. Many federal, state and local permits are required before construction begins. The program manager supports the permitting processes and monitors environmental compliance throughout construction. Design. Burns & McDonnell used internal resources to handle most design work, contracting some detailed elements to other firms. Preliminary design work garnered unanimous approval from the Connecticut Siting Council (CSC). Approximately 30% of the MNP was designed before the final budget and schedule were determined. This mode of operation can provide flexibility in budgeting and scheduling. Under conventional project approaches, modifications to the project can be costly and time consuming. Procurement. Project risk is heightened by competition for construction labor from major transmission projects elsewhere. To reduce this risk, the program management team has met with vendors, gathered data and analyzed market trends to keep its contracting strategy flexible. Mitigating risk is also critical in securing materials and equipment. For example, long-lead major materials and equipment were procured independent of construction to reduce scheduling risk. The 345-kV transmission cable is being specified and procured on the worldwide market. To limit manufacturing risk, no single vendor is allowed to supply the total amount of transmission cable needed, with overall cable quantities being divided into smaller lots to maintain delivery schedules, secure optimal pricing and mitigate risk. Community relations. Community relations play an important

4 SYSTEMUpgrade The new 345-kV terminal in the Scovill Rock Switching Station in Middletown, Connecticut, will be the first completed substation of the Middletown-Norwalk Project. role for the utility. This project has three full-time public relations professionals in Connecticut working with CL&P s corporate communications staff and utilizing CL&P s lessons learned to respond to public inquiries. They also meet with stakeholders to explain project details. A tollfree number and project website provides the public with an immediate avenue for project contact. Safety. Burns & McDonnell is conducting safety orientation to every person working on-site. Four full-time safety managers continually monitor the project and mitigate any safety concerns that develop along the way. The contract with CL&P is incentive based, providing financial rewards for maintaining high safety standards and, conversely, penalties for a poor safety record. Project controls. A complex financial, scheduling and change management system designed to collect and report on submittals, requests for information, drawings, meeting minutes and public feedback is in place to keep the project on schedule and help control costs. Primavera Systems P3e/c is used to track and report on the schedule. Expedition version 10.0 provides documentation for all project decisions and tracks project funding, costs and contract information based on CL&P s cost-accounting structures. Both software systems are Web-based, allowing authorized users to access the system from anywhere, anytime. Construction management. Burns & McDonnell will manage more than 50 different material and construction packages, including thousands of construction workers. The project will peak at more than 600 construction workers on-site. The construction manager is responsible for coordinating between contractors, the contracting strategies, change orders, the overall schedule, daily inspection and quality control. Bond Brothers (Everett, Massachusetts, U.S.) has been selected as the civil contractor for the underground transmission. PAR Electric (Kansas City, Missouri) has been selected as the contractor for the overhead portion of the project. Quality assurance/quality control. Requirements such as construction monitoring, safety, communications, construction records maintenance, receipt inspection of owner-supplied materials, ROW inspections and work completion inspections have been outlined. PROGRAM MANAGEMENT IN ACTION In April 2005, the MNP received Connecticut Siting Council (CSC) approval, but part of that decision required the project to reach out to the municipalities along the overhead construction path for additional input regarding the 345-kV overhead line design. CL&P was required to readdress public concerns, modify designs accordingly and submit detailed construction plans for CSC approval. This process lengthened the design phase and, under another project delivery method, could have delayed the overall schedule and increased costs. Since program management emphasizes overall project completion, not individual components, other aspects moved forward while the additional design issues were being addressed. The first in a series of CSC overhead construction plan approvals came in late 2005, and the last one was approved in late summer Successful program management is as much about managing overall project risk as it is about managing schedules and costs. Program management fits well with CL&P s development risk management program, allowing characterization and mitigations of risks associated with committing to a $1 billion construction project. During early negotiations with CL&P, the utility requested that a portion of the program manager s professional fee be placed at risk, based on a combination of project drivers such as schedule, budget, and safety and community relations. CL&P matched the at-risk fees in an escrow account set up to provide incentive for high performance. Avoiding all risk is impossible, but program management attempts to limit unknowns. A risk matrix identified the most complex part of the MNP as the underground construction, much of which will run directly beneath U.S. Route 1, a fourlane divided highway that is a major commercial artery and crosses several major bodies of water in southwest Connecticut. Installation of the underground cable will require, at a minimum, the excavation of a 4-ft-wide by 8-ft-deep (1.2-m by 2.4-m) trench for duct-bank placement. The complexity of underground construction is due in part to the amount of subsurface rock that must be removed. When the project is in full swing, standby costs for excavation crews are expected to run tens of thousands per day, translating into millions of dollars in additional construction costs should the project encounter significant rock or unexpected subsurface utilities. To mitigate this risk, extensive geotechnical investigations assessed subsurface conditions. Preconstruction testing allowed better assessment of costs and possible delays. The prime civil contractor is providing upfront comments on design alternatives and risk forecasting, to make sure there are no surprises during construction. OVERALL PROJECT BENEFITS Owners reap several benefits from program management on large, complex

5 SPOTLIGHT ON UNDERGROUND The amount of underground transmission on this project makes it one of the most complex projects being constructed today. The following are some of the underground issues being addressed. Splice Vaults. Splice vault locations are determined by cable-pulling calculations, cable reel lengths, existing utilities, system grounding method, and the locations of rock or water or railroad crossings. The vaults have 8 ft by 8 ft by 30 ft (2.4 m by 2.4 m by 9.1 m) inside dimensions and will be spaced about every 1700 ft (518 m) along the 18.5-mile (29-km) total length of underground line. Each splice vault is precast, multisectioned and watertight. The vaults are approximately 30,000 lb per section with two sections per vault. The splice vaults are grounded and contain predrilled holes for the electric and communication ducts that will be racked on one side of the vault. Cable manufacturers specified the inside vault dimensions based on construction, maintenance and National Electric Safety Code requirements. The splice vaults will be supplied by regional precasters using custom structural designs and will have 10-inch to 12-inch (254- mm to 305-mm) thick walls. (Vault design was the subject of a T&D World article Design and Test 345-kV Cable Vaults in May 2006.) Duct Bank Installation. The civil contractor is installing 50 ft to 150 ft (15 m to 45 m) of duct bank per day per crew and will run 10 to 12 vault and duct bank crews at the peak of construction. Two to three supporting crews will be employed for utility relocation, repaving and rock coring. Minimal rock is expected and blasting is not being used. The minimum size of the duct bank is 3.5 ft by 2.5 ft (1.1 m by 0.8 m) and includes horizontal and vertical curves to avoid existing utilities, buildings and landscaping. These curves increase pulling tensions, which decreases cable cut lengths. Installation includes saw cutting the road, excavating the trench, exporting the spoils, placing 10-ft (3-m) lengths of 8-inch (203-mm) PVC conduits in spacers, encasing the ducts in 2500-psi (17-Mpa) concrete, backfilling the trench with a thermally tested flowable fill and laying a temporary bituminous patch. The concrete and flowable fill will undergo thermal testing and slump testing in the field. Fluidized thermal backfill (FTB) is a diggable concrete of 100 psi to 150 psi (690 kpa to 1034 kpa) that allows heat to transfer from the energized conductors inside the duct bank, minimizing cable ampacity losses. After the FTB is placed 19 inches (483 mm) below the surface, the civil contractor applies a 10-inch (254-mm) layer of base rock and a 9-inch (229-mm) layer of class 1 and class 3 asphalt concrete hot mix as a temporary patch. The permanent pavement restoration occurs later. Upon completion of the duct banks, the civil contractor will proof the integrity of individual polyvinyl chloride (PVC) ducts by a robotic video check, swabbing and mandreling. The civil contractor then installs a mule tape to show the exact length of the in-place individual duct bank. Cable Pulling. Burns & McDonnell prequalified and selected, through competitive bidding, vendors to manufacture the four 345-kV circuits. They are Silec Cable, LS Cable and Prysmian Cable. The manufacturers are responsible for furnishing and installing the cable system. The cable for the MNP is a kcmil copper conductor with 345-kV cross-linked polyethylene (XLPE) insulation. The cable is jointly specified by CL&P and United Illuminating (New Haven, Connecticut). Three cables, weighing approximately 29 lb/ft each (209 kg/m), will carry up to 860 MVA. Maximum allowable pulling tension on the cable is approximately 21,000 lb (9500 kg), and average tension during pulling will be between 5000 to 15,000 lb (2300 to 6800 kg). Conduits are lubricated with a soap-like slurry product to lower the coefficient of friction from 0.3 (dry) to values as low as 0.1. Underground trench (duct bank) in Westport, Connecticut, showing three 8-inch PVC conduits, which will later carry the XLPE cables, and one 4-inch PVC multiduct for fiber-optic communication lines. Same as above, but with additional set of conduits for second circuit in background. In underground trench (duct bank) in Fairfield, Connecticut, conduits are encased in concrete for protection and to aid in heat dissipation.

6 SYSTEMUpgrade A KEY FIRST STEP Burns & McDonnell hired GZA GeoEnvironmental Inc. (Norwood, Massachusetts, U.S.) to conduct geotechnical investigations along the proposed underground transmission line route. Work began in early September 2005 and was substantially completed in April The geologic and hydrogeologic properties that would affect the project costs and schedule in the design and construction phases were determined. Depth to groundwater, depth to rock and rock coring to determine subsurface cross-section profiles were completed. More than 150 borings ranging in depth from 14 to 100 ft (4 m to 30 m) were completed during the investigation. Draft boring logs were ed by GZA to Burns & McDonnell within two days of drilling activities to facilitate decision making as the project data became available. Geotechnical engineering reports were issued in phases to comply with the program management schedule in time for RFPs issued for civil/construction activities. A crew obtains core samples along the line route in Fairfield, Connecticut. certified project manager. bartoab@nu.com Jim Hogan is the director of engineering for the Burns & McDonnell Transmission & Distribution Group. At the completion of the siting process for the Middletown to Norwalk Project in 2005, Hogan assumed the role of engineering manager and assistant program manager in the Kansas City office. Hogan is a professional engineer and holds bachelor s and master s degrees in civil engineering from the University of Missouri-Columbia. jhogan@burnsmcd.com Excavator removes existing concrete and pavement prior to underground trenching of duct bank in Fairfield, Connecticut. capital projects. They maintain control over the design, budget and construction processes while relying on the program manager for overall execution. The owner is freed from the requirements of hiring additional staff. Flexibility is inherent in the process, from inception through completion. A sudden change of scope or project approach is accommodated by the methodology. An owner locked into a lump-sum EPC contract, where scope schedule and price are fixed, faces difficulties implementing changes. Program managers work with owners and have a portion of their fee at risk, motivating them to work in the owner s best interest. CL&P recently selected Burns & Mc- Donnell to provide the program management of a related effort, the Glenbrook Cables Project, which consists of constructing 9 miles (14 km) of 115-kV underground transmission to connect the Glenbrook and Norwalk substations in Connecticut. Anne Bartosewicz is a project director for Northeast Utilities, where she is responsible for the Middletown to Norwalk Transmission Project. She holds a bachelor s degree in chemical engineering from the University of Connecticut and an MBA from the University of Hartford. Bartosewicz is a J. Brett Williams, a program manager for Burns & McDonnell, has worked on major-scale design-build and program management projects for the past 16 years. His expertise is in project scope development, design management and construction management from project inception through closeout. Williams holds a bachelor s degree in construction engineering technology from Pittsburg State University and a master s degree in construction science from the University of Oklahoma. jbwilliams@burnsmcd.com For more information, please contact Mike Beehler at Reprinted with permission from the February 2007 issue of Transmission & Distribution World ( Copyright 2007, Penton Business Media. All rights reserved. TD-150-EKK